GB2281158B - Ladder-type filter - Google Patents

Ladder-type filter

Info

Publication number
GB2281158B
GB2281158B GB9416607A GB9416607A GB2281158B GB 2281158 B GB2281158 B GB 2281158B GB 9416607 A GB9416607 A GB 9416607A GB 9416607 A GB9416607 A GB 9416607A GB 2281158 B GB2281158 B GB 2281158B
Authority
GB
United Kingdom
Prior art keywords
ladder
type filter
filter
type
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
GB9416607A
Other versions
GB2281158A (en
GB9416607D0 (en
Inventor
Hiroaki Kaida
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Murata Manufacturing Co Ltd
Original Assignee
Murata Manufacturing Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Murata Manufacturing Co Ltd filed Critical Murata Manufacturing Co Ltd
Publication of GB9416607D0 publication Critical patent/GB9416607D0/en
Publication of GB2281158A publication Critical patent/GB2281158A/en
Application granted granted Critical
Publication of GB2281158B publication Critical patent/GB2281158B/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezo-electric or electrostrictive material
    • H03H9/56—Monolithic crystal filters
    • H03H9/562—Monolithic crystal filters comprising a ceramic piezoelectric layer
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/02007—Details of bulk acoustic wave devices
    • H03H9/02157—Dimensional parameters, e.g. ratio between two dimension parameters, length, width or thickness
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/05—Holders; Supports
    • H03H9/0595—Holders; Supports the holder support and resonator being formed in one body
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/05—Holders; Supports
    • H03H9/10—Mounting in enclosures
    • H03H9/1007—Mounting in enclosures for bulk acoustic wave [BAW] devices
    • H03H9/1035—Mounting in enclosures for bulk acoustic wave [BAW] devices the enclosure being defined by two sealing substrates sandwiching the piezoelectric layer of the BAW device
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
    • H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
    • H03H9/177—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator of the energy-trap type
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezo-electric or electrostrictive material
    • H03H9/58—Multiple crystal filters
    • H03H9/581—Multiple crystal filters comprising ceramic piezoelectric layers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezo-electric or electrostrictive material
    • H03H9/58—Multiple crystal filters
    • H03H9/60—Electric coupling means therefor
    • H03H9/605—Electric coupling means therefor consisting of a ladder configuration
GB9416607A 1993-08-17 1994-08-17 Ladder-type filter Expired - Lifetime GB2281158B (en)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP20342693 1993-08-17
JP21858593 1993-09-02
JP24457093 1993-09-30
JP24456993 1993-09-30
JP24718293 1993-10-01
JP31628293 1993-12-16

Publications (3)

Publication Number Publication Date
GB9416607D0 GB9416607D0 (en) 1994-10-12
GB2281158A GB2281158A (en) 1995-02-22
GB2281158B true GB2281158B (en) 1997-10-29

Family

ID=27553793

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9416607A Expired - Lifetime GB2281158B (en) 1993-08-17 1994-08-17 Ladder-type filter

Country Status (4)

Country Link
US (3) US5648746A (en)
CN (1) CN1065380C (en)
DE (1) DE4429139C2 (en)
GB (1) GB2281158B (en)

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JP3266031B2 (en) * 1996-04-18 2002-03-18 株式会社村田製作所 Piezoelectric resonator and electronic component using the same
JP3271517B2 (en) * 1996-04-05 2002-04-02 株式会社村田製作所 Piezoelectric resonator and electronic component using the same
US6016024A (en) * 1996-04-05 2000-01-18 Murata Manufacturing Co., Ltd. Piezoelectric component
US5939819A (en) * 1996-04-18 1999-08-17 Murata Manufacturing Co., Ltd. Electronic component and ladder filter
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JPH1084244A (en) * 1996-07-18 1998-03-31 Murata Mfg Co Ltd Piezoelectric resonator and electronic component using it
JP3271541B2 (en) * 1996-07-26 2002-04-02 株式会社村田製作所 Piezoelectric resonator and electronic component using the same
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JPH10126203A (en) * 1996-08-27 1998-05-15 Murata Mfg Co Ltd Piezoelectric resonator and electronic component using it
JP3267171B2 (en) * 1996-09-12 2002-03-18 株式会社村田製作所 Piezoelectric resonator and electronic component using the same
JPH10126202A (en) * 1996-10-23 1998-05-15 Murata Mfg Co Ltd Piezoelectric resonator and electronic component using it
JP3271538B2 (en) * 1996-11-28 2002-04-02 株式会社村田製作所 Piezoelectric resonator and electronic component using the same
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JP2005286992A (en) * 2004-03-02 2005-10-13 Seiko Epson Corp Piezoelectric oscillating piece, piezoelectric vibrator, and piezoelectric oscillator
US7492241B2 (en) 2005-06-02 2009-02-17 The Regents Of The University Of California Contour-mode piezoelectric micromechanical resonators
JP4908156B2 (en) * 2006-11-10 2012-04-04 株式会社日立製作所 Thin film piezoelectric vibrator, thin film piezoelectric bulk wave resonator and high frequency filter using the same
WO2008081767A1 (en) * 2006-12-27 2008-07-10 Murata Manufacturing Co., Ltd. Piezoelectric valve
US8493744B2 (en) * 2007-04-03 2013-07-23 Tdk Corporation Surface mount devices with minimum lead inductance and methods of manufacturing the same
US8174170B1 (en) * 2009-05-13 2012-05-08 Sand 9, Inc. Methods and apparatus for mechanical resonating structures
US8513863B2 (en) 2009-06-11 2013-08-20 Qualcomm Mems Technologies, Inc. Piezoelectric resonator with two layers
US9935670B2 (en) 2013-09-26 2018-04-03 Qorvo Us, Inc. Carrier aggregation using multiple antennas
US9985682B2 (en) * 2013-10-24 2018-05-29 Qorvo Us, Inc. Broadband isolation low-loss ISM/MB-HB tunable diplexer
US9899986B2 (en) * 2013-10-24 2018-02-20 Qoro US, Inc. RF diplexer
KR101534645B1 (en) * 2014-08-19 2015-07-09 주식회사 이노칩테크놀로지 Piezoelectric device and electronic device having the same
WO2016194562A1 (en) * 2015-05-29 2016-12-08 株式会社村田製作所 Piezoelectric vibrator and method for manufacturing same
CN111639395B (en) * 2020-05-26 2023-07-04 成都运达科技股份有限公司 Device and method for acquiring vibration information of vehicle under transverse track expansion

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Also Published As

Publication number Publication date
GB2281158A (en) 1995-02-22
DE4429139A1 (en) 1995-02-23
US5644274A (en) 1997-07-01
US5648746A (en) 1997-07-15
CN1065380C (en) 2001-05-02
DE4429139C2 (en) 1998-06-04
CN1105489A (en) 1995-07-19
GB9416607D0 (en) 1994-10-12
US5696472A (en) 1997-12-09

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Legal Events

Date Code Title Description
PE20 Patent expired after termination of 20 years

Expiry date: 20140816